1. Field of the Invention
The present invention generally relates to a method of forming a semiconductor device and a semiconductor device. More specifically, the present invention relates to a method of forming a semiconductor device including a capacitor such as a crown capacitor and a semiconductor device including a capacitor such as a crown capacitor.
Priority is claimed on Japanese Patent Application No. 2007-315050, filed Dec. 5, 2007, the content of which is incorporated herein by reference.
2. Description of the Related Art
Dynamic random access memories (DRAMs) have an memory cell array that include memory cells. Each memory cell includes a switching transistor and a capacitor. There has been risen the problem with decreasing the capacitance due to shrinkage of the memory cell that can be realized by the advanced micro-processing technique.
For example. Japanese Unexamined Patent Application, First Publications, Nos. 11-317504, 2005-229097, 2006-135261, and 2006-245364 each address a semiconductor device including a crown capacitor and a method of forming the semiconductor device. The crown capacitor would be suitable to ensure the adequate capacitance with allowing shrinkage of the memory cell. Particularly, Japanese Unexamined Patent Application, First Publication, No. 2005-229097 discloses as follows. A cylinder hole is formed in a dummy oxide film. A bottom electrode is formed on the inside wall of the cylinder hole of the dummy oxide film. The bottom electrode has a bottom-closed cylinder shape. The dummy oxide film is removed, while the bottom electrode resides. It is necessary to prevent the bottom electrode from being collapsed. A supporter is provided to support the bottom electrode and to prevent the bottom electrode from being collapsed. In general, the dummy oxide film is removed by a wet etching process. The wet etching process is carried out using chemicals. The chemicals have a surface-tension that causes the formation of a short circuit between two adjacent bottom electrodes, thereby causing the defects of bit-pairs or bit-groups of the memory. The supporter is effective to prevent the formation of a short circuit between two adjacent bottom electrodes.